Process and apparatus for treating liquids.



E. W. DEMING.

Patented Feb. 4, 1913.

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BY I 7 1 I g w n wm ATTORNEYS E. W. DBMING.

PROCESS AND APPARATUS FOR TREATING LIQUIDS.

APPLICATION FILED APR. 13, 190B.

1,95%,220. Patented Feb. 4, 1913.

3 SEEETS-SHEET 2 r id A TTORNE Y5 E. W. DEMING. PROCESS AND APPARATUS FOR TREATING LIQUIDS.

APPLICATION FILED APR.13, 190B.

Patented Feb.4, 1913.

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% 7: 67pm, @Wue A TTORNE Y8 cinrrnn stares r nrnnr orrrcn- EUGE E W. DEMING, on NEW YORK, N. Y., AssIoivon T0 Beams APPARATU coivrrA'NY, or NEW ronK, n. Y., A CORPORATION 01? NEW YORK.

PROCESS AND APPARATUS FOR TREATTNG LIQUIDS.

Specification of Letters Patent.

Patented rob. 4,1913;

Application filed April 13, 1808 Serial No. 426,900.

preparatory to separating suspended solids therefrom.

I to the treatment or defecation of sugar solu tem involving continuous flow.

from the crushing rolls contain and persist- I 'tigins or the like and will be described by reference to this application, it being understood thatithe invention is capable of use in other relations; i I

It is well understood that in the clarificationor purification of sugar cane juices much difliculty is ek'perienced in the separation of solid matters, principally the fibers of the cane and the precipitate resulting from the action of heat andof the reagents, such sulfur dioxid and lime, used for clarification. According to modernpractice the cane juices from the crushing rolls, after passing through a strainer for the separation of coarse fiber, are treated with sulfur dioxid.

and lime or other suitablereagents and are thereafter heated to or above their atmospheric boiling point while flowing under appropriate pressure through a system of heating tubes. The solids are then separated bysettling or filtration or by a combination of these methods. Preferably the highly heated juices containing the suspended solids pass, either before or after cooling to or below the atmospheric boiling point, to a continuous-flow separating device, usually a tank from which the Clea: portions of the juice overflow while the separated solids are continuously Withdrawn to filter presses or the like. v

The specific gravity of the solids is but;

slightly greater than that of the juices and cult and usually incomplete under any sys- The uices The invention is particularly applicable ently retain a large proportion of dissolved andmechanically held-air, and in the aftertreatment of the juices other gases are'produced. When the juices are heated under pressure in a closed system no opportunity is alforded for the escape of these gases, and

after cooling, to a device. for separating the in case the juices are conducted directly, or

solids, the gases liberated Within the body of liquid interfere seriously with the separating operation, retardingor preventing the downward movement of the suspended particles and even conveying a considerableproportion of these to the surface.- These gases also interfere seriously with the operation of the filter presses, reducing their capacity.

'I have now discovered that the continu ous separation of the solids'is rendered mu:

tively easy of accomplishment by the pro vision between the heating and separating.

devices of means for eliminating all or substantially all of the contained gases.

One form of apparatus embodying my in, vention is illustrated in the accompanying drawings Wl18I'8iI1-.-

Figure 1 is a diagrammatic elevation showing an apparatus for treating sugar cane uices, this apparatus comprising a heater or digester for the raw juice, a gas eliminator, a reheater for the degasified juice and a continuousfiow separating tank; Fig. is a vertical axial section on an enlarged s ale of the gas elii'ninator, and Fig. 3 is an axial section of the eliminator in a plane at right angles to that of Fig.

he eliminator A as illustrated in 'Fig. 1 arranged to receive the juice from the crushing rolls, after treatment with sulfur dioxid and lime or'other appropriate reagents, through a supply pipe 1' leadingto a surface condenser 2 in the upper part of the eliminator. A; discharge pipe 3 leads from this condenser to a heater or digester Bzby which the solution is brought to a suitable. tempe 'ature which may equal or exceed the atmospheric boiling point. From this heater the juice passes through a pipe 4 and'adustablv-wei 'hted ressure-reducin valve 5 into the eliminator A, which in the formshown comprises a closed tank liaving-cyiii. drica-l sides and converging bottom. A. pipe 6 leads from the bottom of the liminator to a circulating pump (1 which delivers the degasified juice through pipes T, S, 9 to a con tinuous-fiow separating tank E. which may be of the character described in my prior Patent 885,450 granted April 21, 1908, or of any other suitable type. From this separator the purified nice passes through pipe 10 to the evaporator-s.

1) represents a reh-ater for use in case it is desired to raise the temperature of the degasitied juice before separating the solids therefrom. The heater B, pump C and reheater I) may be of any conventional and Well known construction.

The eliminator A, shown in detail in Figs; 2 and 3, comprises a cylindrical tank 11, preferably of sheet-steel, having'a 60 conical bottom l2-leading to the discharge pipe 6. A surface-condenser and juice-preheater 2 is arranged in the upper part of the tank, and comprises a number of horizontal pipes 13, usually of copper, extending transversely across the space in the upper part of the tank and connected to cast-iron heads 14, 15 outside the tank, the juice received through pipe 1 traveling back and forth through the pipes 13 and finally out through pipe 3. Beneath the pipes 13 and riveted to the sides of the tank or other wise supported therein is a trough or pan 16 which receives the condensate produced by contact of the hot vapors with the relatively cold outer surfaces of the pipes 13. A. pipe17 leads from the bottom of the pan 16 for the discharge of this condensate.

The juice containing suspended solids, preheated in its passage through the pipes 13, is raised to the proper temperature in the heater B and, passing the pressure-reducing valve 5, is delivered into a horizontal annular tube 18 of copper, having a perforated lower wall, within the tank 11 and just above its conical bottom. The hot juice delivered through the perforations accumulates in the tank to a level indicated by the line 19, the air and other gases escaping freely from its upper surface, and the liquid then passing out through the pipe 6 below. A pipe 20 leads from the head at the top of the closed tank to a vacuum pump, not shown, and this pump cooperates with the surface condenser 13 to produce a partial vacuum in the upper part of the tank, the air and other gases readily escaping from the surface of the hot liquid below into the partially-exhausted space above.

The steam pump C, serving to withdraw the degasified liquid from the eliminator and deliver it to the separator E, has a steam supply valve 21' which is controlledadd-ll 1 by a, lever and this le er is actuated, through a link 23, crank 24;, rock-shaft 25,

"crank 26 and link 27, or other suitable mechanism, by a vertically-movable float 28, pariaily submerged in the liquid in the tank.

This float has a central guide-tube 29 slidmg on a vertical fixed rod 30. The float. so controls the supply of steam to the pump C as to maintain the surface 19 of the liquid at asubstantially constant level.

In operating the apparatus for the treat ment of cane juices these are preferably although not necessarily heated in the digester B to a temperature somewhat exceeding the atmospheric boiling point, an appropriate pressure being maintained by the valve 5. If juices so heated were permitted to escape into an open vessel their temperature would at once fall to the atmospheric boiling point, a proportion of wiiter corresponding to the change of temperature temperature will fall to a point corresponding to the boiling point under such diminished pressure, vapor being formed as above. The effect of the gas-eliminator herein described, when operatedin connection with a heater for the raw juice, is to condense these vapors by transferring heat therefrom to the juice flowing to the heater or digester, thereby conserving this heat; at the same time the gases carried by the heated juice are removed with substantial completeness, and the subsequent separation of the solids is-facilitated as above pointed out. Obviously also there occurs a concentration of the juices corresponding to the amount of condensate removed through pipe 17. It will be apparent that by a proper adjustment between the temperature of the juice passing from the digester B and the pressure within the eliminator A, such adjustment being at all times within the corn trol of the operator, any desired proportuni of the heat from the juices entering the tank 11 may be transferred to the incoming juice flowing through the pipes 13, at the same time that the heated juices are degasified. 'tis further apparent that the eliminator i'nay be operated at normal pressures or at pressures either above or below normal in accordance with the requirements of any particular case. the fixed gases being removed through the pipe 20 and the vapors of water or'any desired proportion of these particular conditions: thus when the juice liquid in transit and subject to deterioration from inversion, fermentation and other causes.

In the drawings. I have indicated such relation between the float 28 and the liquid inlet'18 to the eliminator A that the. liquid is introduced beneath the normal liquid level in, the eliminator. The posit-ion of the float is however readily adjusted, and its position may be altered as required to. meet eXlubits a strong tendency to foam in the eliminator the liquid level therein may be I Carried below the inlet 18, the latter being raised if necessary, in order that the foam may be beaten down by the inflowing streams of liquid. Should the liquid flow-' ing from the pipe 17 contain appreciable proportions ofsugar it maybe used for saturation at the milling plant or otherwise treated to avoid loss.

1 claim:

1 The continuous process of separatingsuspended solids from liquids, which consists in heatin the liquid under pressure,

, then reducing t e pressure to separate therefrom the dissolved or mechanically retained gases, and finally separating the solids by gravity from a flowing column of the gas free liquid.

.2; The continuous. process of separatingsuspended solids from liquids, which consists in heating the liquid under pressure, then reducing the pressure to convert a portion of; the liquid into steamand to separate from the residual liquid the dissolved or mechanically retained gases, effecting a heat-interchange between the steam and the liquid passingto' the 'heater, and finally sep-.

arat-ing the solids by gravity from a flowing column of the gas-free liquid. :3. The continuous process of separating suspended solids from liquids, .which consists in heating the liquid under pressure, then reducing the pressure to a degree be-v low that of the atmosphere to convert a portion of the liquid into steam and to separate from the residual liquid the dissolved or mechanically retained gases, eflect-ing a lib heat-interchange between the steam and the liquid passing to the heater, and finally separatin the solids by gravity from a flowing co umn of the gas-free liquid.

4, Apparatus for treating liquids carrying solids in suspension, comprising in comwination a liquid-heater, a continuous-flow separating tank for suspended solids, a closed gas-eliminator, pipe connections he'- tween said gas-eliminator and said llqu1dheater and separating tank, and a surface condenser located in'the vapor space of the gas-eliminator.

5. Apparatus hination a; i'quldrheater, a' continuous-flow p for treating liquids carry" jiiifgweolids in'puspension, comprlsmg 111 com- ,j'gg nt i higher pressure.

separating tank for suspended. solids, a closed gas-eliminator having a surface con denser located in its vapor space, pipe connections between said gas-eliminator and said liquid-heater and separating tank, and a pipe connection between said surface condenser angl said liquid-heater;

' 6. In apparatus .for treating liquids carrying solids in suspension, a gas-eliminator comprising a closedtank having a liquidinlet and outlet, and an outlet. for fixed,

gases, means for maintaining a constant liquid level within said tank, and a surface condenser in operative connection with said tank.

7. Inv apparatus for treating liquids carrying solids in suspension, a gas-eliminator comprising a closed tank having a liquid inlet and outlet and'an out-let for fixed gases, a distributer for the inflowing liquid, and a surface condenser comprising tubes disposed in the upper portion of said tank.

8. In apparatus for treating liquids carrying solids in suspension, a gas-eliminator comprising a closed tankhaving a liquid means for maintaining a constant liquid levelwithin said tank, a surface condenser comprising tubes disposed inthe upper portion of said t-anlgand means for collecting the condensate and conveying it from said 12. The process of defecating sugar juices which, comprises heating said juices under pressure to produce defecation, exposing the hot juices to a less pressure to permit evolution 'of gas and vapors while condensing said vaporsto aid in the maintenance of such less pressure and settling under 1a 13. The process of defecatingv sugar juices which comprises heating said juices 'under pressure. to produce defecation, exposing the hot juices to a partial vacuum to permit evo- I lution of gas and vapors while condensing inlet and outlet and an outlet for fixed gases.

said vapors to aid in the maintenance'of 14. Theprooess of defecating' sugar w i h Comprises heating said juices under;

such vacuum,- and settling under atmospheric pressure; 1

pressure to produce defecation, exposing; the hot j uices to a partial vacuum to permit evolution of gas and vapors While condensing said vapors by juice in. transit to the heating operation whereby aid in the maintenance of the vacuum is afforded and heat is recovered, and settling under atn'iospheric pressure. I

15. The process of detecatinc; sugar juices which compries heating; said juices under pressure to produce defecation, e Kposin; the hot uices to a vacuum. to permit evolu'tum of gas and vapors and contacting the produped vapors with ajuicecooled heat-int-er changing Wall to condense the same and aid in maintenance of vacuum and settling under atmospheric pressure.

1G. The continuous process of treating liquids carrying solids in suspension, which consists in heating; the liquid under pressure to produce separated solids, then separating dissolved or mechanically held gases by a reduction or pressure and finally separating the solids from the gastree liquid by gravity at ahigher pressure than that prevailing in the gas separatingstages.

1.7. The continuous process of treating; liquids carrying solids in suspension, which consists in heating the liquid under pressure to produce separated solids, reducing the pressure and therebv separating dissolved or mechanically held. gases, and iinally separating the solids from the gas-tree liquid by gravity under a. greater pressure.

18.".ihe continuous process of treating liquids carrying solids in suspension, which consists in heating" the liquid under pressure to produce separated solids, reducing the pressure and thereby separating dissolved or mechanically held gases and vaporizing Water, transferring heat from the said and vapor to the liquid to be treated, and finally separating; the solids from the gastree liquid under a greater pressure.

19. The continuous process of treating liquids carrying solids in suspension, which cons' .ts in heating the liquid under pressure to produce' separated solids, reducing the pressure and thereby separating" dissolved or mechanically held gases and vaporizing water, transferring heat from said gas and vapor to the liquid to be treated, and finally separating; the solids from the gastree liquid by gravity under a greater pressure.

20. In a detecat-ing apparatus, the combination of means for heating; juice under plus pressure, means for settling the heated juice, and intermediate means for exposing the juice to l pressure than prevails in the settling means, all said means being pipe connected and operating on the juice in continuous transit;

21. ln a defecating a 'iparatus, the conibination of pipe connected means for heating juice under plus pressure, means for exposinpj the heated juice to a less pressure and means for again raising the pressure and permitting settling; of solids.

in a detecating apparatus, the combination of pipe connected means for heating juice under plus pressure, mean for exposing the hot juice to a "va cuum, means for settling the juice at ordinarypressure and pipe connections between said means.

23. A detecatinp; apparatus comprising a superheater for juice, a source of supply of juice under pressure therefor, a Vacuum chamber receiving juice from t the super-- heater, a condenser receiving vapors from said chamber and fed with cooling juice from said source, and settling means receiving" juice from said chamber and pipe con.- ncctio-ns thereto.

24. A defecating' apparatus comprising a juice supcrl'ieatcr. a vacuum chamber and a settling chamber pipe connected in series and treating: juice successively in continuous transit. and a preliminary heater delivering;

juice to said superheater and receiving va-,

pors from said vacuum chamber. V I 25. A detecating' apparatus comprising a i nice preheater, a juice super-heater, a vacnum chamberand a settling chamber pipe connected in series and treating juice successively incontinuous transit and means for heating the juicein the preliminary heater by vapors from the vacuum chamber. In testimony whereof, l. aiiix my signature in presence of two witnesses.

EUGEX'E ll. DEMTNG.

ll'it-nesscs:

K. V. lJiXCIIARl), Emvp. Knnxi. 

